Based on comparative case studies of Apple Computers strategic actions in the music and cellular telephony industries, we develop the concept of cross-boundary disruptor as a new type of entrepreneurial actor in inter-industry strategic dynamics. We document how the confluence of forces that drove the convergence of the music and computing industries gave rise to Apple Computer becoming a defining example of a cross-boundary disruptor to the music industry, and examine Apples chances to do the same in the cellular telephony industry. Using our preliminary conceptual framework, we further examine what kind of company could become a cross-boundary disruptor in the US healthcare industry to help overcome its long-standing stasis. We summarize our case study-based findings into a preliminary substantive theory of the cross-boundary disruption phenomenon, and discuss several implications for further strategic entrepreneurship research and for strategic leadership practice.